TY JOUR TI A Method for Monitoring the Availability of Required Navigation Performance for Locomotive Satellite Navigation Equipment KW satellite navigation KW availability monitoring KW required navigation performance KW railway transport KW positioning error dispersion ellipse KW railway automation and remote control devicess JO Transport automation research AU Demyanov, V.V. AU Loginov, D.D. PY 2026 IS 12 PB FSBEI HE "Emperor Alexander I St. Petersburg State Transport University"